New Girl
by Sweeterthansugar
Summary: Based on the 2012 show on Nick. April has made it obvious she doesn't want to pursue something with Donnie, so Donatello is pretty upset. As he's outside thinking about the girl he's had a crush on for forever, a new and strange girl comes staggering out of the woods. Is she a friend or a foe? Who exactly is she? Takes place after season 2 before season 3. Rated T just to be safe.
1. Mysterious arrival

**Chapter 1: Mysterious arrival**

**So basically this takes place after the second season, before the third. Just a little idea I had watching the season 2 ending. Hope you enjoy!**

* * *

><p>Ragged breathing sounded in the empty catacombs as paws raced through dry, crinkled wrappers and other assorted trash. Like a shadow, the creature moved through the black tunnels, pausing to catch its breath. Its nose worked, smelling the air, then it raced down a tunnel. Finally, it arrived at a large man that wasn't a man. He may have worn a rat's skin, but his soul was that of a man. The large beast paced alongside him for a moment before nudging his side. The scent of snake blossomed out of his soaking wet clothes at the gesture. With a growl, the beast backed up.<p>

"Uhhh..." Splinter stirred and grasped his head. "Where...?" His eyes caught the creature beside him. It appeared to be a large dog, but as his eyes adjusted he realized the bulging muscles and size didn't belong to a dog. "A...wolf?" At his voice, the wolf lowered its head, whining as if in agreement. Splinter sat up and gazed steadily at the creature. It appeared to be a typical wolf, though larger than he'd expect because the beast before him seemed easily strong and large enough to carry a small person, though still small enough to pass as a large dog. He held out a paw and the wolf sniffed. After a moment it licked his paw, then it startled him by nearly pouncing on him and licking at his fur where his injuries were. He pushed against it, trying to get the creature off him, but as he did, he noticed his injuries seemed to hurt less. Splinter drew his paws away from the wolf's scruff and they came away damp. It's coat, wet with the sewer mist and sweat, was pure black except a slightly lighter shade around its jaw and belly, but he could tell that wouldn't matter if this wolf wished to hide in the shadows. "Why are you here?" Its eyes flicked up to his, gold intelligent eyes that surprised him. It made a soft huffing noise, but he had no idea what that meant. "I must find my sons." The wolf watched him with a steady gaze, its ears twitching as if listening for enemies. Splinter stood, but groaned and the wolf moved to help him stand. "Thank you..." He noticed its tail wag slightly at the comment, but its eyes were still filled with worry.

"It's not safe here, you know. It should go against all of your animal instincts to be in a city, especially a city invested with Kraang." His brow furrowed as he reconsidered. "On top of that...why would you be in the sewers?" All the wolf offered was a tilt of its head, as if it was curious. "Perhaps...do you know the way out?" The wolf spun and padded off silently. Hamato Yoshi hurried after the furry shadow. They walked silent and slow, constantly pausing due to Splinter's injuries. He noticed that the wolf paused whenever he needed it to and that while he caught his breath it would sniff the air and its ears would twitch as it searched for enemies. Finally, Splinter saw a dim light ahead. He stepped out and stepped down a small ledge as water poured from the sewer into a small stream. The man walked to the bank and laid in the grass, his chest heaving as he stared up at a sliver of moon in the sky. It was hardly a strand of its full crescent. "It is a beautiful night. Thank you..." He looked around, but the wolf, his guide, was no where to be seen.

* * *

><p>Donnie sighed as he went outside. It was a crisp, cool night, but he liked it. Besides, it was nearly over, day was approaching. Even though the sun was minutes away, there was still a coolness in the air that only the night could summon. It sharpened his brain and senses, though he wouldn't mind them dulled a bit right now. Now that Leo was doing a lot better, still not back to his old self because some of the damage, like his throat, which was beyond his current skills, but better nonetheless, his mind had time to wonder. Naturally, it kept wandering back to April and one of their last encounters in New York. He kept thinking back to when he had finally got up the courage to tell April his feelings, but before he could, a look of apprehension had crossed her face and she had quickly changed the subject. If that didn't scream one-sided crush, he didn't know what did.<p>

Donatello sighed again and stared out at the clouds. It was hard not to keep thinking about April when she was one of the five other people here, excluding ice cream kitty. She also seemed to be hanging around Casey more and more ever since his near confession. He looked out at the slowly appearing sun as a breeze came and blew from behind him, making the ends of his mask tickle his cheek.

If it weren't for that breeze, he may not have heard the voice. He had started to turn when the breeze caught his mask and he had paused to tuck it back behind his head before turning back to the house.

"...help..."

Donnie froze and listened. "...is...meone...ere...?" The voice seemed so weak. He had heard it coming from the forest so he took off in that direction. As the turtle approached the sound, the sun seemed to lazily crawl up the sky, as if too sleepy to start the day yet, and it seemed to darken the forest beneath it. He glanced among the darkened trees and saw the silhouette of a figure staggering out of the trees. Donnie's eyes widened in surprise and he made it in time to catch the figure as he saw the small form fluttering to the ground.

His arms caught a rather small teenage girl, she'd maybe come to his shoulder if she were standing and was rather skinny. Though the turtle's face warmed as he realized when he had caught her one hand had landed on her butt and the other had brushed her chest. She had passed out so ironically it was bad she had passed out, yet he was grateful she hadn't been awake for it because it had been purely accidental. Because of this, noticed she was fairly curvy, though not overly so. He quickly fixed his hands and lifted her up, carrying her back to the house. As he walked, he took in the girl's appearance. Her clothes were fairly wet, from what he assumed to be her sweat based on the fact that she seemed perfectly healthy except for her ragged breathing from what he guessed was over exertion, or so it appeared. She had on a black fitted sweatshirt with quite a few pockets, the hood of it brushed his arm as he walked, and loose black pants that ended with small sneakered feet. Her skin was fairly pale, nearly a ghostly white, and her hair was a wild, thick mess of black atop her head.

Donnie worked open the door to the barn, careful to support her limp body the whole time. He had picked the barn because it was closer and it doubled as his workshop and laboratory. He laid the girl on a makeshift cot, being as gentle as possible. She stirred slightly, almost snuggling against him and he froze, but then she lay limp again and he quickly freed his arms and scurried to his desk's chair. "Who are you...?" He was answered with silence other than her slightly calmer breathing.

It slowly dawned on the ninja that he ought to check her over and make sure she wasn't injured. Donnie swallowed nervously. Slowly, he slid her pants up her legs far enough to check for bruises or cuts. He was surprised to see they were fairly muscular, as far as a female's leg was concerned, but they seemed alright. Donatello slid her pants' legs back down and moved up to her sweatshirt. With another swallow, he unzipped it and carefully slid it off her. This time she didn't stir at all at the movement, which concerned him a bit, but her breathing and pulse were normal. Under her sweatshirt was a very tight, and rather low cut, black tank top. He noticed she had some strange circles up her arms too. Gingerly, Donnie lifted her arm and inspected a circle near her wrist. There seemed to be nothing unusually about them, they looked like a tattoo or something, so he put her arm back down. Maybe she'd tell him about them when she woke up. If she woke up...

Donnie laid a thin blanket over her and turned back to his desk to clean some of his clutter. He lost track of time when he was cleaning and lost himself in the task so when a soft voice spoke, it nearly made him jump out of his shell. "Who are you...?" He spun around expecting an amused expression at his surprise, but she was just watching him with shy curiosity. What surprised him more than that was her eyes. They were a strange color. If he had to pick a color he'd say they were golden, but he didn't think humans could have golden eyes. Oh well. Food for thought for later.

"My name is Donatello, but my friends call me Donnie." The teen moved his chair closer and she didn't object so he slid it until he was sitting right beside her. "What's your name?" His question made her brow furrow.

It was as if someone was telling her to think of something she hadn't needed to know in ages, like an old song name. "My...name..." It wasn't a question. She was searching her memory, but it still worried Donnie, until her eyes flashed with recognition. "My name...it's Erin." She smiled at him and it was such an innocent warm smile he had to smile in return.

Erin moved to climb off the cot, but instantly staggered. Quick as the ninja he was, Donnie caught her shoulders. "Easy... I'm not exactly sure what happened, but it's obvious you over exerted yourself. Rest here for a little bit and we'll figure things out when you wake up."

He honestly expected her to argue, the refusal was right there in her eyes, but then he felt her shoulders sag under his hands and she nodded gratefully. "Thank you..."

Erin climbed back under the blanket and laid on her side facing him, watching him closely. "Are you staying here because of me...? Please don't. I'd feel bad..."

He laughed softly. "Don't worry. I've pulled quite a few hours in my lab. You're not forcing me to be here. Besides, it's early enough for me to be awake, but everyone else is late sleepers."

"So why are you up so early then...?"

"Because I like to see the sunrise."

It was an innocent answer, but something flashed across her eyes before she nodded. "Yeah...me too." Then the girl pulled the blanket up to her chin and nodded off almost immediately. He watched her peaceful sleep for a few moments before he went back to his tinkering, quiet as a mouse.

* * *

><p><strong>So there is chapter 1! Rather short I know, but I like the first chapter to be short to see what people think. Hopefully you liked it! So please review and tell me what ya thought(good or bad)! Thank you! See ya soon! <strong>


	2. Full of surprises

**Chapter 2: Full of surprises**

* * *

><p>Donnie fiddled with one of his inventions when he heard a soft sigh from behind him. He spun around and looked at the cot. The girl was yawning, sitting up in the bed. Her hair was a frizzy mess from sleep and he couldn't help, but laugh a little. She paused as she rubbed her eye and turned to him, lowering her hand. Her eyes were immediately focused on him intently, like a curious animal. The intensity of her gaze caught him off guard and he turned back to his invention shyly. He heard a soft shuffling behind him, then her voice was at his ear. "What's that?" She seemed genuinely curious, compared to the others that asked to be polite if they asked at all that was.<p>

"It's a tracking machine." He held up a small tube. "You shoot the tracker out of here and then this machine here will track where it goes." Donnie saw her nodding along out of the corner of his eye.

"That's interesting." She picked up the tracking chip and gazed at it. "You may want to put some kind of waterproof layer and more grips in case what it's attached to moves fast or through water."

Huh. Donatello hadn't thought of that... "That's interesting...oh! There's this new gel I've been meaning to try." He immediately began to search the work space for the sample. Erin smiled and giggled at his excitement. Donnie kept searching, but his hands fumbled as he felt his face warm at the noise. Her looks seemed kind of tough, more of a tomboy, so the giggle was rather unsuspected. Come to think of it...it wasn't often he made April laugh like that, so hearing a girl's light laugh like that was an unexpected treat. He was glad he was turned away so she couldn't see his cheeks turn red.

Erin moved and sat in his chair, smiling sweetly and making it turn back and forth on its swivel innocently, something that no one else he knew would do. Donnie smiled back, sample forgotten for the moment. She was really different from April, the only other human girl he knew, and he couldn't decide whether that was good or bad...or how he felt about it.

* * *

><p>Breakfast in the house was a fairly cooperative task. Leo moved around Raph and poured some orange juice as his brother fried some sausages. Mikey hummed as he set out plates and utensils. "Awwww yea, boy!" He grinned as he checked on the sausages. "They're done!" Raphael rolled his eyes at his brother's enthusiasm and put the sausages on plates.<p>

The oldest turtle brother looked around. "Hey, has anyone seen Donnie?" Both of the other present brothers shook their heads as April and Casey walked into the kitchen.

April slid into her seat at the table. "He isn't in his room either." The group seemed to ponder where their tech support was when the turtle in question wandered in.

"Hey, guys." Donatello hovered by the door, looking around nervously.

"Stop standing in the doorway and come help." Raphael looked at his brother in irritation.

"Ummm...guys? Before I do...I have a surprise."

Mikey jumped over the counter and grinned at his brother. "What kind of surprise, my brother?"

"Welllll..." Donnie lifted his arm and Erin peeked around his shell shyly. He was extremely aware of her hand nervously resting on his shell. "It's small and female?"

"H...hi..." Her voice came out soft and the room froze. Everyone's eyes widened and the room felt silent except for the soft hum of the fridge and the sizzling of the frying pan.

"Donnie! Who is that?! What's she...?!" Leo raised a hand, silencing his younger brother.

"Raph. Quiet." Leo approached and Erin nervously clung to Donnie's side, making him keep his arm raised as well as making his heart rate raise. "Hello. I'm Leo. Who are you?" He smiled encouragingly and she gave a shy smile back. The small girl glanced up at Donatello and at his nod, she answered.

"My name is Erin. Your brother, Donnie...he helped me."

Leo nodded and cleared his throat before he introduced everyone and she gave a smile or nod at each name. After Leo had said the last name, Mikey sprung forward. He stared at her with an uncharacteristic intensity. "I have a very important question for you..." Erin stared at him, wide eyed, looking like she might bolt from the room. "Do you like sausage for breakfast?"

Erin smiled happily, looking relieved, her whole body relaxing, and she nodded. "Yeah! Especially with eggs." Mikey grinned and draped an arm across her shoulders, pulling her into the kitchen.

"Well, you haven't had _my_ eggs!" He began to talk to her about his cooking techniques and she listened with what was definitely more than just polite interest. From the door, Donnie smiled at how well the new girl seemed to be fitting in. He didn't think it'd go this quick or this smooth. He distantly heard Mikey saying he'd make eggs just for Erin and saying how the two of them would have to make a cake later because he hadn't had cake in forever. Usually he didn't have much of a sweet tooth, but when Mikey suggested they decorate it to look like a pizza, it seemed to make more sense. Raphael even slipped into the conversation saying he wanted a chocolate cake.

As the trio chatted as Mikey made eggs, Donnie noticed Casey and April talking together at the table. He sighed, but when Leo put a hand on his shoulder and gestured to the other room, Donnie put all else from mind. Leonardo coughed and then they headed into the family room.

Leonardo regarded his brother and spoke in a soft voice so the others didn't hear. "Okay. Tell me everything that happened, Donnie." With a deep breath, Donatello launched into the tale of how he had met Erin and taken her to the barn. He mentioned the odd tattoos and how she had only rested a short bit before she seemed to be at full energy, even though she had been exhausted when she had met him. The turtles' leader listened intently and waited until Donnie was finished until he responded. "She seems like she could use some help, but we don't know much about her. April thought she could trust Irma and look how that turned out." The pair fell silent as they realized the weight of what Leo had just said. He cleared his throat and started to cough. Donnie's eyes filled with worry, but he was waved off. "I'm fine..."

"No, you're not. I should start on some new medicine as soon as I..."

"...excuse me?" The two teens turned to the hesitant voice and saw Erin glancing between them. Her eyes seemed to linger on Donnie, looking at him like he was her security blanket. Then she stepped towards Leo. "I heard you coughing..." She held out her slender hands, which held a glass of orange juice with ice cubes clicking off the sides like chimes.

The turtles exchanged surprised faces then Leo smiled and accepted the glass. "Thank you." He drank it heartily and she beamed happily.

"All the food is ready, so whenever you guys are done talking maybe we could all eat together?" There was a hopeful note in her voice as if nothing would make her happier than a family meal.

"Sure. I'm starved." Donnie gave her a smile, but she looked away shyly, though he wasn't sure why. The trio shuffled into the kitchen to eat.

* * *

><p>"So you're all ninja?" Erin was perched on a log as Donatello and the others got ready to start sparring.<p>

"Uh huh. Our sensei, Master Splinter, raised us as his sons and when he raised us he taught us ninjutsu."

Erin watched him stretch and a playful look crossed her face. "Bet I could still take you."

The turtle paused and glanced at her. "It wouldn't be very fair. I've trained my whole life to be a ninja."

He bent over to touch his toes and heard the faint hiss of a zipper and as he stood back up there was the faint thud of something hitting the ground. Donnie turned and saw Erin had taken off her sweatshirt and now took a ready stance. "I love a challenge."

A wind blew through the small clearing as Donatello noticed everyone else was already sparring. Raph was taking on Mikey and Casey, while April and Leo sparred. The purple masked turtle of the group turned back to Erin. "Alright. I won't be too tough on you, though." He pulled out his staff and twirled it before launching at the smaller girl. She rolled to the side then pounced at him. Erin missed, landing on all fours, but she seemed at ease in the position and as Donnie rushed at her, she planted her hands firmly and kicked his chest. He staggered back as she ran at him. Donatello held up his staff defensively, but Erin swept his feet out from under him and grabbed his staff as he fell. With a thud, Donnie was on his back and Erin had followed him down. She sat straddling his chest firmly. They both held on to his staff and, because it had landed over his head, Erin's face was close to his.

"Told you..." Her eyes stared like they always seemed to, but this time they only stared at him, refusing to look away shyly like they had every other time.

Finally, after forever, Donnie found his voice. "Gu...guess ya did..." Erin grinned, but this time it was different. Her smile wasn't as shy, but Donnie couldn't find the right adjective for it and before he could thoroughly search his brain for the word, she had stood and offered him a hand. He grasped her hand and stood. It was surprisingly soft and cool in his hand. "Well, _that_ was a surprise. I really shouldn't have gone easy on you..."

Erin grinned. "Nope. You're not the only one with a few moves after all." The pair stood for a moment and a faint blush began to creep into Erin's cheeks. "Umm...Donnie? You can let go of my hand now..." A mortified Donatello dropped her hand, realizing he was still holding it. She laughed and again it sounded light and innocent, like tinkling chimes.

There was a thud nearby and they looked up as Raph began walking over, Mikey and Casey sprawled on the ground. "Yeah, but that was only Donnie. Why not try a real challenge?"A smug smirk was firmly planted on his mouth.

"Hey!" Donnie fumed at his brother.

"Hey, you said yourself you'd go easy on her. _I _wouldn't underestimate anyone like that, especially someone that I don't know how tough they are."

Erin laughed again softly at their brotherly bantering and smiled, a challenge in her golden eyes. "Bring it on, Raphael." As Erin and Raphael launched themselves at one another, Donatello went back to sit on the log and watch. She really was pretty good. He could see her movements weren't made out of haste or desperation. Erin wasn't just jumping out of the way or blindly attacking. She knew what she was doing. Raph still got in a few good moves of his own, her skills weren't at Splinter's level after all, but she easily held her own against their best fighter.

"Mind if I watch too?" The turtle looked to the side as April sat down beside him. Apparently, Mikey and Casey had some fight left in them because the two of them were now sparring with Leo.

"No. Go ahead..." Donnie was very aware there were only a couple feet between him and April.

"She's pretty good." Donatello nodded along as he saw Raph block one of her kicks and toss her aside. "Doesn't she seem a little...too good?" He turned to her, a questioning look on his face, so April elaborated. "Well, she's clearly been trained how to fight and the timing of her coming out of the woods...doesn't it seem a bit strange to you?"

"Not really. Strange stuff happens to us all the time." Raph threw a punch, and Erin grabbed his arm, slipping under it.

"Donnie." April's voice was firm, which surprised him. "We know nothing about her. Yeah, she's pretty, but we don't know that..." Donnie zoned out as he heard what she had said. She sounded almost...jealous? For some reason, that just made him irritated.

"April." He cut her off, his voice equally firm. "I tried to tell you how I felt back in New York, but you didn't want to hear it. I'm not saying I've moved on, not by a long shot, but Erin makes me smile, makes all of us smile, actually. That's something none of us have been doing a lot of lately. If she's dangerous, well, we'll keep an eye on her, but she's something good that's happened to the team." As he spoke, Erin jumped behind Raphael and pounced on his shell, but he grabbed her wrist and threw her down. After a moment, he helped her stand, clearly impressed. She wiped her forehead then glanced at Donnie. When she saw him looking, the girl raised a hand in an enthusiastic wave. Donatello felt his frown shift into a smile as he gave a wave back.

April sighed. "I just think she's bad news." The redhead wandered back to where the other three members of their group had finished and were chatting. Donne noticed with a pang how she automatically went to Casey's side. What he had said was true, but he still had a very serious crush on April.

"Did you see?!" He jumped and turned to where Raphael and Erin were approaching. "I think I did really well. Raph said so too, right, Raph?"

"You did okay." He gave a small, impressed smile and she squealed happily.

"Yay! I knew I would do well!"

"You did really well." Donnie smiled down at her. Her happiness was rather infectious.

"C'mon, guys!" The trio turned to where Mikey was shouting from. "Let's go have some pizza! I worked up such an appetite!"

* * *

><p>"Yummmm..." Erin was nestled in an armchair that made her look positively puny, but extremely cozy as she ate her slice. A stubborn strand of cheese kept the pizza and her mouth firmly connected. After a bit of attempting to sever it, it broke and Erin licked the gooey cheese off her lips. "Mmmm..."<p>

"Haven't you had pizza before?" Casey so bluntly remarked.

"Mmm mmm." Erin shook her head and swallowed. "Nope, but it's really tasty."

"Oh, man! Never had a pizza?!" Mikey stared at her, eyes perfectly round. "How can such horrors happen in the world...?" Erin giggled then took another bite. "If you've never had pizza before you have to have something more exciting than Leo's extra cheese!"

"I happen to think extra cheese is really good." Leo shoved his brother's shoulder affectionately.

"Nah, bro. She needs to have something like meat lover's or stuffed crust. Something interesting. Hmmm..." Mikey never got more serious than when it came to pizza.

"Why do I always get stuck on the floor?" They looked up as Donnie returned with another slice. April and Casey were seated on the couch, a bit too close for his taste, with Raph on the third cushion. Leo and Erin each occupied an armchair, while Mikey sat in his reserved space, down in front by the TV.

"You can have my seat, Donnie." Erin got up.

"I don't want to steal your seat, especially stealing a girl's seat? It's just rude."

"Don't be silly. There's room for two." Donatello immediately had images of Erin snuggled up against him in his mind, but then saw she had settled on the arm of the armchair, one leg dangling off, swinging lightly. He came over and sat, still very close to her nonetheless. "Happy?"

"Very." Donnie smiled at her then quickly looked around the room, trying to make it look like he was implying everyone eating together made him happy.

"Shhhhh! It's starting!" Mikey stared at the TV as Crognard the Barbarian appeared on the screen.

The group watched for a few minutes then Erin leaned close to Donnie's ear to whisper. "I don't think I've seen Mikey blink once since the theme song..."

The turtle had to focus at not shivering as her breath tickled his skin. Donnie turned his head and whispered back into her ear. "It's a physical impossibility...then again it is, Mikey." Erin clamped a hand over her mouth to stifle a laugh.

As the commercials came on, Mikey stood to grab more pizza and Erin started to get up too, only to knock her uneaten slice on to the chair. "Oh my gosh! I'm so sor..."

"Pizza!" Mikey jumped forward as if someone was falling off a cliff. He shifted the cushion away from the chair and carefully extracted the slice. "I've got you. The mean lady can't hurt you anymore." He regarded Erin with disdain. "I'm taking this because you clearly can't be trusted with its safety."

"By all means..." Mikey gobbled the slice up and as he was chewing, he noticed a small notch between the cushion and the side of the chair he had exposed. "Wazz tat?"

April glanced at where he pointed. "Oh, I forgot. That chair is also a recliner, but it's old so I don't know if it will still recline."

"Let's find out!" Mikey grabbed the notch and moved it, making the chair buck. He jumped back with a yelp as the chair shot into a reclined position, making Donnie fall back in surprise and Erin to fall off the arm on to his lap. "Demon chair!" Mikey pointed at the chair looking scared.

The group laughed at the same time the occupants of the recliner realized what had happened. "Donnie, I'm so sorry. I..."

"It's okay." Donnie sat back up in the chair and Erin looked away shyly as Donnie's face warmed. She _was _still on his lap after all.

Leo spoke up then. "Well, since it's almost night, after this episode how about..."

"It's almost night?!" Erin's eyes had gone wide as she looked around for a window. Seeing the sun slipping out of the sky, her eyes widened more. "I...I have to go!" She bounded out of Donnie's lap and ran for the door.

"What was that all about?" Casey looked at Donnie, eyebrows raised.

"I have no idea... Erin! Wait!" Donatello took off after the girl.

* * *

><p>Outside, he caught her in no time. His arm loved around her upper arm firmly, but not hard enough to hurt her "Erin! What's going on?!"<p>

The girl uselessly tried to tug her arm out of his grasp. "Please, Donnie... Let me go!" Her eyes frantically searched for the sun and they widened as she she saw how low it was in the sky. The way she was acting was similar to how a scared animal may act when faced with a hungry predator or how a pizza may feel up against Mikey.

"Not until you tell me what's going on. Is it because Mikey's goofing around made you fall on my lap? It was an accident. It's okay." Donnie felt part of him hurt at this, but now wasn't the time to wallow in that.

"No! No, it's not that." For a second, she stopped trying to shove his hand away and looked up at him. "That was..." Something in her face made Donnie's heart race until a low moan escaped her lips and she slumped to the ground.

"Erin!" Donnie looked her over, panicked.

She looked up at him and rested a hand on his cheek for a moment. "I didn't want you to see...but since you will I have to tell you. It'll still be me. For about a minute, my brain is murky, like when you found me, but then it'll clear and it'll be me. It's also only until morning...so you can ask me any and all questions then...okay...?" She gave a tired smile before her body gave a violent shake as the sun disappeared from view.

"Erin! What's happening? What can I do?" The turtle's worried eyes met her sad ones.

"Just understand that...it's still me...because during the time...I can't speak..." She began to shake. "That's the part I miss most...my voice..." Then her body shook so hard, she slipped from Donnie's arms to the soft grass. In an instant, her black clothes had shifted and seemed to turn to hair. She fell to all fours, which were now paws. Her face stretched to become a muzzle. A tail sprung forth.

Donnie stared in shock as he stared at where Erin had been not even thirty seconds before. In her place, stood a large black wolf, its eyes closed. It shook out its coat then looked at him, eyelids sliding back and Donnie saw gold, intelligent eyes sitting in the wolf's face. Wolves often had golden eyes, he knew this, but these eyes were different. They were intelligent and worried. "...Erin...?" His voice came out a whisper, although he had meant it to be louder. The wolf simply nodded.

* * *

><p><strong>Well, there's chapter two guys! Hope ya liked it. I'm sure a lot of you have picked up that Erin is a possible love interest for Donnie. Based on feedback, she may become his definite love interest or just a crushing friend and April moves into being Donnie's girl. So please share! Is it good so far? Bad? Tell me how you feel! I love reviews so please please please read and review! Thanks!<strong>


	3. Lone wolf

**Hey there guys! Real quick note here. I've managed to get out a few chapters in the span of just a couple days, but I'm kinda losing the vibe due to it doesn't seem like this is a fan favorite. So since this chapter has a bit of a twist hopefully it draws some attention. If not, then maybe I'll wrap this one up. Up to you! I write for the fans! Now on with the show!**

* * *

><p><strong>Chapter 3 Lone wolf<strong>

* * *

><p>"Erin...?" Donnie reached out a hand and she stepped forward, nudging her snout into his hand with a low whine. Her nose was moist and he could feel her warm exhale blow against his hand.<p>

"Donnie! Erin!" Leo called their names, but the others quickly joined in and the pair could hear them approaching.

Erin whimpered, her ears drooping and she backed up, looking like she may flee. "Hey, it's okay. You know they're friends..." Erin nodded, but she still looked like a flight risk. Donatello reached forward and rubbed the fur of her neck. It was soft and warm beneath his palm. She crooned at the gesture and her tail wagged a bit. "It'll be okay. I'm right here." Her ears pricked up and she nodded, moving close to him and seeming a bit more relaxed.

"There you are!" Donnie and Erin turned to the approaching group. Mikey was the first to see Erin in her hairy new form.

"Wolf!" He dropped the slice of pizza he had and darted behind Raph.

"No! It's okay!" Donatello stood up and raised his hands up. "She won't hurt you."

"She?" April looked between her friend and his four legged companion. Erin whimpered and pressed against his side.

"I know this will be hard to believe..." As he spoke, Erin slinked forward, ears pinned back nervously. She gingerly picked up the piece of pizza Mikey had dropped in her teeth and raised it up to him. "...but that's Erin."

The other turtles and humans were quiet for a second before they burst with surprise. "WHAT?!" Well, everyone except for Mikey, who had taken the pizza Erin offered him and was chewing on it happily.

* * *

><p>"I'm not exactly sure how it works. She told me she can't talk when she's a wolf before she changed." The group had gathered in the barn as Donnie explained what had happened. He had also taken a small sample of her DNA and was currently analyzing it. "Odd..."<p>

"What is, Donnie?" Leo got up from where he'd been slouched against a bale of hay. Erin had been curled up against him and her eyes fluttered open at his movement. She raised her head, ears pricked, as she watched everyone.

"Her cells." Donatello raised his head from the lenses and shook his head in confusion. "The closest comparison I can make is to solar panels. My guess is the way her cells are designed, the sun gives her body energy to stay in her human form. When the sun sets, she becomes a wolf. It'd sort of explain why she only had to rest a little bit before she felt fully rested too." As he spoke, Erin got up and padded over to his chair, laying down again beside his feet. Her body was warm and he smiled at how at ease she now seemed. It seemed she was perfectly fine being a wolf and all her nervousness had been generated by what she thought they may thing of her little secret. "If I could analyze them deeper it may be that the moon affects her blood somehow. If its pull can affect oceans it may affect her mutant blood. Do you know why you change this way?" Erin shook her head and shrugged, a very human gesture that seemed odd to see when she did it in her wolf form.

April crossed her arms. "See? There's so much we don't know about her. It's not safe to keep her around." Erin's ears pressed back and she moved to lay in the shadows under the desk. Her fur brushed against Donnie's toes. He wondered if she was touching him faintly so he knew she was still there, but it wasn't like she could tell him one way or the other.

Leo stepped in before the wolf's guardian turtle could speak up on her behalf. "From what Donnie said, it sounds like she was worried what we may think of her turning into a wolf. Everyone has secrets and this isn't necessarily a bad one. It looks like she still has her human brain even when she's a wolf, so she won't just attack us or something." Erin rumbled her agreement against Donnie's feet.

The youngest turthe brother got down on his hands and knees and peered into the dark at their friend. "Come out, little wolfette...you saved my pizza so you're a friend in my book!" Mikey shined a flashlight under the desk and saw Erin's tail was wagging happily at his statement and she watched him with an intense gaze. "Besides, what animal would fit in better with ninjas than a wolf?" Everyone seemed curious what she may do, but then the wolf's nose sniffed and she moved out from under the desk, happily licking Mikey's cheek. The boy laughed and she seemed to smile. He draped one of his arms over her neck and it was a very bizarre sight. A boy and his dog, a tale as old as time, except the boy was a mutant turtle and the dog was a mutant werewolf. "Yep! You'll fit in just fine." She barked her agreement.

Leo rested a hand on his brother's shoulder. "Well, now that that's decided how about we go get some sleep?" There were assorted agreeable comments and slowly everyone filed out of the barn. Leo was ready to close the door when he saw Erin had paused to stare at Donnie who had gone back to his microscope. "Coming, Donnie?"

"Not just yet, Leo. I want to look at these cells a bit longer."

Leonardo nodded. He didn't quite understand why his younger brother was so obsessed with science, but he did know by now that when Donnie wanted to figure something out, he wouldn't stop until he had. "Alright. Just don't push yourself too much." He glanced down at the wolf looking between the turtles. "Erin? Mind staying and making sure he gets some sleep?" She nodded, her tail wagging enthusiastically. He smiled and closed the door behind him. Everyone knew of Donnie's intense crush on April and Leo knew Donnie still had feelings for their resident kunoichi, but maybe this new girl would be good for him, one way or another.

Erin darted over to where Donnie sat and she sat beside him. He hardly even seemed to know she was there so after a few minutes she laid down and rested her chin on her paws. She must have dozed off because after a while she opened her eyes that seemed sticky with sleep. The wolf's jaws opened widely as she yawned. She scratched behind an ear with a paw then turned to Donatello. He was now glancing at the microscope then scrawling on a pad. It seemed like he hadn't moved at all. A glance at the clock revealed he should have been in bed long ago.

Erin whined and rested her chin on his thigh. She gazed up at him with sad puppy dog eyes. After a few minutes of his ignoring her, she got frustrated and leaned up, snatching his pad off the desk in her teeth and running off with it. "Hey! Erin! Come back here!" She dropped it on his bed and gave him a stern look, which was pretty easy for a wolf to do. He shook his head. "I have some more work to do before bed." With a growl she charged forward and knocked his legs out from under him, making him fall on his bed. He started to get up so she pressed her paws to his chest, growling at him angrily so he'd stay down. "Fine. Fine. I'll get some sleep."

Erin nodded. She made a growling noise that Donnie had no hope of translating. What the girl was thinking was that she was happy just to finally have friends. She was happy to have something resembling a family, even if only for a moment. It hadn't been long that she had been pulled into their group, but she was already on cloud nine. Just to have friends and be liked...it was more than she could have ever hoped. The wolf walked to the door, nudging it open and slipped outside. She wouldn't be able to get Donnie to sleep, he'd be up in about five minutes to venture back to his microscope, she could tell, but maybe there was something else she could do to help the group...

* * *

><p>As April slept, the door was nudged open and silently a figure found its way to beside her bed. Piercing eyes stared at her in the dark. Slowly, a tentacle like appendage slid up and pushed against her shirt sleeve. The girl made a soft sound in her sleep and rolled over.<p>

In her dream, she walked through a dense fog. "Hello? Is anyone there?" April searched around until a voice made her jump.

"Hey, April." The redhead spun to face the other girl. "Can I have a minute?"

The girl crossed her arms, but nodded. "I guess..."

Erin smiled. "Thanks. I just need to tell you something." She took a deep breath. "I didn't come here to get in the way. I was tired from a long trip and I needed to make sure you guys were here and were safe." She brushed some hair behind her ear. "I have a confession. I'm not the giggling shy girl that I've been acting like. I was told it would help me befriend you faster and it did just that. Well, except for you, right, April?" She smiled wryly and it seemed true about her change of character. Her stance, a hand casually resting on a hip and her narrowed eyes, screamed smug confidence compared to the shy skittish creature she had been earlier.

April wasn't exactly sure what Erin was talking about. "Then why the act? And why lead Donnie on?"

"I didn't lead him on!" Erin unclenched her hands and sighed. "Sorry. I have a bit of a temper. It was hard to hide. Due to my...condition...it's a challenge to make friends. Donnie was the first person in a very long time to reach out to me. It meant something. So yeah. I flirted a little, but I wasn't lying. We all just met, but I care about you guys. Donnie was my first friend in so long... I felt especially close to him. I kind of screwed things up and I get it, but I want to make it right."

"How do you plan on doing that?" April felt unexpectedly guilty at her slightly hostile behavior towards the girl prior to this conversation.

Erin didn't answer. Instead she ran a hand through her hair and smiled at the other girl. "I was so awkward with you guys. I've silently observed countless couples and friends interacting, but rarely actually done so myself, interacted that is. It was strange...my sudden connections to people, having friends, it was a lot to handle. I'm sorry, April, and I'm not a fan of apologizing so know that I mean it." She turned as if to leave, then paused. "By the way...from what I've grasped of the situation, you don't want to pursue things with Donnie because you're afraid if things sour it may ruin your friendship, right? Well, do what you like, but you'll never know until you try. Do you really want to wonder 'what if' for the rest of your life?" Then the girl disappeared into the fog.

"Erin! Wait!" April began to chase after her, but it soon became obvious she would never reach the other girl.

"Wait!" April sat straight up in bed with a gasp. She looked around her room, but it was entirely empty...

* * *

><p>Erin's nose smelled the air, pausing for a moment. She was one of the biggest, toughest, and most vicious creatures in these woods, but better safe than sorry. The wolf took off again and finally after what seemed like forever, she reached the place she was looking for.<p>

"You've returned so quickly." She turned, panting, to the large figure that entered the clearing. "Please. Have a drink and rest before anything else.

It had been late when she had left, later than she would have liked, so she had just finished drinking from the nearby stream, when the sun began to rise. With a low groan, the wolf changed back into a girl. She stretched and looked over at the shadow. Somehow he didn't seem surprised by her change. "You knew I was a werewolf?"

"I could sense conflicting auras surrounding your presence." Erin didn't quite follow, so she just shrugged.

"Well, either way. Want to see them again?"

He nodded. "I would love to see them. Come. Let us journey there...together this time."

Erin nodded. "Yes...but there's something I must do first."

"Oh?" He raised an eyebrow at the werewolf.

Erin nodded and looked at the man carefully. "I have to find Karai..."

The man's usually calm demeanor fractured for a moment. "Karai...? Why do you need her?"

"Well, for one, the family at that farmhouse won't be complete until she's found. For another...I need some of her..." The girl looked at the sun that still hung low in the sky. It'd be a while until she was a wolf again so her senses would be dulled, but they'd still be incredibly sharper than any average human's would be. "...some of her blood..."

Immediately, his eyes narrowed. It was rarely a good thing when someone needed blood from someone. Erin saw and sighed. "Look, I'll extract it painlessly." She slid her sleeve up a bit and one of the tentacle appendages slid from the exposed circle on her arm. It was the same color as mutagen and seemed to be a tube-like thing with a dome shaped tip, making it look less intimidating. "I can control these making them do things that I need them to do, to a degree. For example, right now I need them to..." It shot out and pushed against the man's chest. His eyes widened, startled. "Make you sleep." Then the man fell into darkness.

* * *

><p>"Has anyone seen Erin?" Donnie walked into the kitchen and looked around.<p>

The others shook their heads and expressed that they hadn't seen her. Donnie's brow furrowed worriedly, but then a small hand fell on his shoulder. "Erin?!" He spun around and saw a startled April. "Oh, I'm sorry, April. I was looking for Erin. She..."

"Yeah, about that..." The teen girl jumped into her tale of how she had seen Erin in her dream and how the girl had told her she had something she had to do.

"So, it was all an act?!" Raphael thumped his fist on the countertop. "I should have known..."

"Wait a second there, Raph." Leo walked over to April. "April you know we all trust you, but it _was_ a dream after all..."

"No. It was more than that. I can't explain it..." The girl struggled to find the words to describe it.

"Well, the way I see it, she's a traitor. She played us. If she comes back..." Raph twirled a sai before slamming its blade into the cutting board in front of him. The handle wiggled from the force, leaving an eerie noise in the silence that followed his angry outburst.

"That's not fair! I'm sure..." Leo raised a hand up, cutting Donnie off.

_"If..."_ Leo put emphasis on the word. "...she comes back, we will deal with it when that happens. I don't see why she would act like that to lower our defenses because she didn't gain anything of significance from it. So, if she comes back, we'll give her a chance to explain herself and if it's not good enough, then she isn't welcome. Agreed?" April and Mikey agreed with a sigh. Casey agreed nonchalantly. Raph grunted out an annoyed acceptance.

Donnie was hesitant. "But, Leo..."

"Agreed?" Leo looked at his teammate sternly.

Donnie slumped. "Agreed..."

* * *

><p>A short while later, Donatello was sitting in the grass, near where he had first seen Erin as if they would replay their first encounter at any moment. The bushes rustled and he looked up excitedly, until he saw a bunny hop out of the bush. It twitched its nose then darted back into the underbrush. He sighed and put his chin on his hands. Casey seemed indifferent about Erin's leaving, April and Leo seemed bummed, but not overly so, Raph was angry, but it seemed like he was taking it hardest with Mikey not far behind. They had only known her such a short time, yet she fit into their unusual group so easily, it seemed like they had known her their whole lives.<p>

"You really miss her, huh?" The purple masked turtle turned as he heard the voice that belonged to the last person he ever expected to come comfort him.

"Gee, is it that obvious?" Casey sat down near Donnie, balancing a hockey puck on his forearm.

"Pretty much."

"Wow...you're so good at comforting. Do you do it often?" Donatello's eyes narrowed to go along with his sarcastic response.

Casey tossed the puck in the air and caught it. "Chill. Casey Jones doesn't make a habit of being all touchy feely."

With a groan, Donnie rested his forehead on his arm. He was pretty sure it was impossible for this day to get any worse.

Casey stood up and dusted off his pants. "Look, she'll be back before you know it and everything will be fine. You'll be wondering why you were out here moping in no time flat." On that uplifting note, he headed back to the house.

"Hey, Donnie?" Casey and Donnie looked toward the barn as Mikey stuck his head out of the door calling for Donatello. "One of your weird gadgets is making a boop boop boop noise. It's realllllyyy annoying. Can you make it stop?"

The two boys ran to the barn and Donnie gasped. "It's my tracker! Maybe Erin took it with her? Wait. What were you doing in the barn anyway?"

Mikey looked sheepish. "Well, I came in to check on you, but I saw this and it looked cool, so I picked it up, but when i hit the button it started making noise."

"Why would you touch...?" Donnie sighed. "Never mind. Let's get the others."

* * *

><p>"Alright. Let's check it out." The group had gathered in the family room and Leo had carefully listened to Donnie's explanation.<p>

"No way! What if it's a trap?" Raphael looked at his brother in irritation. "We're already debating if she can be trusted and you want to rush to her?"

"But why would she want to lead us to her?" Donnie shook his head. "The tracker hasn't moved. Maybe she's in trouble..."

Leo scanned his friends and brothers. "Alright. Donnie, Casey, and April will stay here in case this is a trap. They can be backup and defend the...base." The word 'base' didn't seem terribly true for the farmhouse, but he charged ahead in his plan anyway. "Raph, Mikey, and I will go check out the tracker."

"Why do I have to stay here?" Donnie looked frustrated as he heard the plan.

"Because you're upset and not thinking clearly." Leo rested a hand on his brother's shoulder and smiled. "We'll call on the t-phone as soon as we find the tracker and whatever it leads us to." His brother seemed slightly pleased by Leo's answer, but was still very clearly bummed. "Mikey. Raph. Let's move out."

* * *

><p>It didn't take the trio too long to reach the location of the tracker. Leo checked the scanner. "It looks like the tracker should be in the clearing up ahead. Stay sharp."<p>

Raph chuckled. "Mikey is never sharp."

"Nope." Mikey rubbed his round head happily. "I'm nice and smooth." Raph facepalmed at this.

"Come on." Leo led his two younger brothers into the clearing. "What the...?! No way!" Raphael's and Michelangelo's eyes widened in shock at what the tracker had led them to.

* * *

><p>"Why haven't they called yet?" Donnie paced in front of the couch that Casey and April were seated on. Casey slouched and absentmindedly flipped through channels.<p>

April looked at the dark screen of the t-phone. It sat silently on the coffee table. "I'm sure they'll call any minute..." She had been saying variations of this same phrase for the past half hour it seemed.

"What if something happened?" Donnie stopped pacing as his always thoughtful mind went into overdrive. "What if Erin had taken the tracker in case we needed to find her and she ran into trouble and now the others are in trouble..."

"Donnie...I'm sure they're fine..."

"Maybe they are. Could be in trouble, though." Both April and Donnie turned to Casey as he dropped that bombshell into the conversation. It didn't seem like much, but someone else acknowledging Donnie's worries were monumental. It meant he wasn't just overreacting, that his ideas were possibilities.

As if on cue, the t-phone lit up, playing its happy little tune. Everyone jumped and Donnie hit the speakerphone. "Leo?! What is it?! What'd you find? Is Erin there?"

"Ummm...not quite, Donnie... Someone else is here instead..."

April leaned forward. "Who's there, Leo?"

There was a soft static sound as the phone was passed to someone else. "Hello, Donatello. April."

Time seemed to come to a crawl as Donnie's and April's eyes went perfectly round. Donnie finally found his voice. "...Master Splinter...?"

* * *

><p><strong>So there is chapter 3! Like I said I'll give it a few days, but if there's not much feedback, I'll wrap this story up. If there's something you guys would like to see or would rather I work on edging out if the story let me know! I can't always work in fan ideas, but I do listen and try to incorporate them. Anywho hope you enjoyed and don't forget to review! Till next time!<strong>


	4. The wolf and the snake

**Chapter 4 The wolf and the snake**

* * *

><p>Erin pulled her hood over her head and slid up her small face mask. She had also slid on fingerless black gloves. The girl stood completely black except for her pale fingers and the pale strip of skin where her golden eyes looked out from.<p>

New York was still infested with invading Kraang so she walked through the woods until she found the sewage tunnel that she had led Splinter out of only a couple of days ago. The girl looked up at the moon that had gained a bit of weight since that night, turning from a mere sliver to a better sized chunk of its full self. With a nervous swallow, the wolf slipped into the sewers to search for the snake.

* * *

><p>"Master Splinter!" April and Donnie rushed out to greet him. Mikey and Raph were helping to support him, since Leo still wasn't at full strength yet.<p>

"Hello, my son. Hello, April." He smiled tiredly at the two teens.

The happiness at Splinter's return was nearly tangible in the air. They brought him inside and settled him on the couch. April brought him a plate of cheese and they all settled around him to hear his tale. They waited a few moments then April spoke up. "So, what happened to you master Splinter? Last we saw you, you and Shredder had fought and he had thrown you into the sewer water. We thought you were gone..."

Splinter nodded. "Yes. I vaguely remember being pulled out of the water and then waking up with a black wolf beside me. It led me out of the sewers and I..."

"Black wolf?!" Everyone looked to Donnie, startled by his outburst. "It had to have been Erin!" As he took in their faces, he smiled sheepishly. "Errr...please continue, sensei."

"Very well. The wolf led me through the sewers to the forest. I was drained from my fight with the shredder, so I rested for some time. Just a few short hours ago, the wolf reappeared and changed into a girl. Perhaps this 'Erin' that you mentioned?"

"Yes! It has to be! Do you know where she is sensei?" Donatello looked at Splinter eagerly.

The man shook his head. "I am sorry, Donatello. I'm afraid we only talked a few moments before she made me fall unconscious."

"See?!" Raph looked at his brothers angrily. "She attacked master Splinter! She can't be trusted!"

"On the contrary, Raphael. She injected me with something that made my body fall unconscious. Although she forced me to lose consciousness, it was in one of the least forceful methods I can imagine." This made Raph fall quiet. He was sullen, but didn't speak up against Erin again.

Leo looked at his sensei. "So where is she now?"

Splinter shook his head. "I do not know. She did, however mention about going after Karai." His brow furrowed as he remembered. "She said she needed some of Karai's blood."

"She needs her blood? Ewww..." Mikey stuck out his tongue in revulsion.

Casey chuckled. "Hardcore..."

April looked at Donnie. "Why would Erin need Karai's blood?"

The turtle shook his head. "I have no idea..." He stood clenching his hands and looked around the room determined. "I'm going after her."

Leo sighed. "Donnie...we've been over this..."

"No. We discussed what we'd do if Erin came back because we didn't know if she was a friend or foe. She saved master Splinter and led us to him! It's obvious she's our friend!" He looked at Leo. Their gazes were steady with neither backing down. "I've never gone against your orders before and I'm not saying you guys should come with me, but I have to help her."

Angrily, Raphael slammed his hands on the table. Mentally, Leo was already going over how to calm Raph down again this time when his brother said something completely out of left field for his character. "Donnie, we're going to go bring her back as soon as Leo makes a plan so stop your whining!"

The room seemed to come to a stand still as everyone processed what he had just said. Leo broke the silence first with a very profound question. "Ummm...what?"

"I said we're going to go get her as soon as you come up with a plan."

Donnie turned to his usually brash and unreasonable brother. "Well, I never thought I'd say this, but...thanks for taking my side, Raph."

"Yeah, yeah." Raphael leaned back and crossed his arms, trying to regain his tough guy image.

Mikey patted Raph's head lovingly. "There's the mopey Raph we all know!" Raph silently glared daggers at his younger brother, making him remove his hand in fear.

After that, everyone seemed to be on the same page. They threw out different ideas on how to find Erin and what to do when they found her. Finally, they decided that Donnie would search the sewers for her and the others would wait not too far away. If he needed help then he'd call on the t-phone. Casey and April would stay with Splinter since he was still fairly weak.

Mikey pouted at Leo. "Why can't I go with Donnie? I miss Erin too!"

It'd be rather complicated to explain to the youngest turtle brother why it was different for Donnie missing her and Mikey missing her. Leo sighed. "Because it's less likely to scare her off. She did basically run away in the middle of the night, Mikey. If too many of us approach her, she may get scared and run off again." Glumly, Mikey looked down so Leo continued. "Besides, I'm sure she misses you and it'll give her motivation to hurry back quicker if Donnie says you're waiting for her." This seemed to do the trick because Mikey's frown did, indeed, turn upside down. "Now. Let's move out."

* * *

><p>Donnie approached the sewage exit slowly. He knew his brothers weren't far away, but being by himself in the sewers below a city invested with Kraang wasn't all that reassuring. There was no turning back, though. Donnie had to save Erin because she saved Splinter and because he...because she saved Splinter. The turtle wasn't willing to look into those feelings, not now. Right now, he had a job to do and to do it he needed a clear head that wasn't being distracted by a confused heart. He took a deep breath of the afternoon air and climbed into the dark.<p>

* * *

><p>Erin's sneakers made light squishing noises in the muck, but besides that she was completely silent. She paused and smelled the air. It was hard to smell with all the sewage for most people, probably counting her reptilian friends, but her nose was sharp and she caught the faint odor of snake here and there. It would go quicker if she was in her wolf form, but this would suffice. Besides, it couldn't take her too long. It was dangerous with so many Kraang moving around on the surface.<p>

Erin frowned as she moved on and held her sleeve to her nose. Due to her mutated state, her sense of smell was so powerful that if there was an extremely strong scent it could make her pass out or light headed and she'd act loopy. Fortunately, despite this being the sewer, the odor wasn't strong enough to do that to her. Although in some corridors, it was strong enough to make her cough and in others it was strong enough to make her want to puke.

She marched along, until the scent of snake got stronger. Erin broke into a run and rounded a corner. The girl stood for a moment wondering where the scent had come from when something shot out of the water and knocked her feet out from under her. "Oof!" The girl landed square on her back and butt, but quickly scrambled to her feet. "What the heck was that?!" She crouched at the edge and peered into the murky water. All she saw through the sludge was a faint reflection. The water was completely still. For what seemed like years, she crouched at the water's edge. Finally, her voice came out in a whisper. "...Karai...?" As if her voice was a trigger, something burst out of the water and wrapped around her middle, pinning her arms to her sides. In an instant, Erin was pinned against the wall. She squirmed, grunting, but then looked at her captor. "Karai." The snake woman stared at her with vacant eyes. "I know you understand me!" She writhed in her grasp. "Let me go and let's talk!"

The snake stared at the wolf for a moment before peeling her scaly tail away from her. She shifted back into a girl more gracefully than when Erin transformed. Karai crossed her arms, eyes narrowed suspiciously. "Then talk."

Erin brushed her hands over her clothes then looked at the girl as she pulled her hood further down over her face. A snake and a wolf in the wild weren't particularly friendly so their animal instincts didn't help them be friends, but Erin still had something she had to do regardless of that fact. "The turtles, your adoptive brothers, have found a safe place. They live in a farmhouse some miles from the city with April, her friend, and your father." At the mention of her father, Karai hissed. "I mean Splinter, not Shredder." Karai seemed startled and she looked away, her tongue flicking between her lips then disappearing back inside her mouth. It was an old habit thinking of Shredder as her father, he'd raised her for roughly sixteen years after all. She had accepted Splinter as her father, but her head was often murky since her transformation. "Come with me...I'll take you to them...you can be with them..."

"I...I can't." The ex-footclan member looked down dejectedly. "I don't belong with them."

"Karai, don't be stupid." The kunoichi looked up in annoyance. "You're Hamato Yoshi's daughter and the adoptive sister of the turtles. You should be with them. There's nothing stopping you from being with them after all, except for your own hesitation."

The girls stared at each other for a long moment before Karai finally spoke. "I..."

"Found you!" The girls looked over startled at where Donatello stood panting at the end of the corridor. His eyes darted to Karai and he gasped. "Karai?! You're human?" His brown eyes took in her fangs and eyes after just a moment. "Sort of..."

The snakewoman seemed to sneer, ready to say something snarky, so the werewolf stepped in. "Donnie! What are you doing here?"

"I came here to bring you back." Erin blinked. He was being rather blunt, considering he was usually one of the shyer turtles. "I don't know why you left, but we know you lead us to master Splinter. Please." Without even thinking, Donnie took one of her hands in both of his, his eyes pleading with her. "We all owe you a lot. Come back to the farmhouse. We need you. I..." He paused and she could see he was struggling to actually say the words, but his eyes had finished the sentence without hesitation.

"Do...Donnie...I..." Erin gazed up at the turtle helplessly. She couldn't voice it either. She needed them too. She needed _him_ too.

"Well, look what I found..." The trio spun around and looked at the other side of the tunnel where Rahzar was grinning at them. "Master Shredder will be extremely pleased I found you, Karai. Oh, and I found his lost little guinea pig too... Maybe I'll tell him while I give him his turtle soup. " He snapped his jaws in Donnie's direction, but Erin stepped in between them. Her eyes glared into Rahzar's challengingly. In the wild, it would be a show of confidence and dominance among animals and Rahzar, in his mutated dog state, could sense it. His eyes widened and his ears dropped.

He was quickly recovering, though. Erin saw his human desire to deal with Donnie and to bring Karai and herself to Shredder covering his animal instincts. His stance mirrored a bull getting ready to charge. There were also footsteps of approaching people from the tunnels behind him. He'd probably have back-up in just a few minutes.

Erin only had a moment. She spoke to Karai without taking her eyes off Rahzar. "Karai." The girl could feel the other girl turn to her as she spoke her name. "Once, you're in the forest, Donnie can lead you to the farmhouse, but I need you to promise me you'll get Donnie out of these sewers whether he likes it or not."

Karai nodded solemnly. She knew Erin's plan, could see it in the girl's eyes. There was a strange kinship she felt with this girl that she had never felt with April. Karai had always felt April to be more a rival, but with Erin it was different. They were both mutants and both had feelings for one of the four turtle brothers. In general, they just seemed more...alike. "I will."

Erin nodded. "Good." The girl took a deep breath. "Good..."

In a flash, Erin was at Donnie's side. She reached out and grabbed the strap across his chest, pulling him close. "Be happy with your family and live a good life with April..." Then she clipped something to the strap.

Donnie looked at her confused. "Erin? What are you...?" But she didn't let him finish. She leaned in, closing the distance, and brushed her lips softly against his. It was such a gentle kiss that he was lingering in the moment from his surprise when she put her hand against his chest.

She whispered to him faintly. "Goodbye, Donatello..." Then she shoved him. Donnie had a moment of looking at her in pure shock before he splashed into the water. Karai dove after him, transforming. She wrapped around Donnie and let the current carry them away. Karai glanced through the water at Erin, the same as Donnie was doing, and saw Erin giving them a sad smile before she would be taken from view.

"ROAR!" Rahzar's roar of fury seemed to make the floor beneath Erin's feet vibrate and then he was racing at her. He'd reach her in just a few seconds.

"It's time you learned who's really top dog!" Erin charged at him and that was the last Donnie and Karai saw her.

They drifted along on the current, until it slowed and they reached the exit. Karai slithered out with Donnie before letting him go and shifting back. She looked at Donatello who was kneeling in the water. "Donnie, I..."

"It's not your fault..." Donnie stood up. "We have to go back."

The girl looked at him sadly. "You heard others coming just as well as I did. By the time we get there, it will be crawling with foot soldiers. We can't go back." Her voice was stern.

Realistically, Donnie knew they couldn't go back, but that didn't lessen the pain he was in. Karai was right, though. The only choice they had at this point was to go back to the farmhouse. He looked at the dark entrance of the tunnel. It was night now and he couldn't see farther than maybe twenty feet in. Somewhere in those dark tunnels a wolf version of Erin was fighting a powerful and fierce Rahzar. That is if she hadn't been captured...or worse... Donnie's voice was so soft that if Karai's hearing hadn't been enhanced from her mutation, she never would have heard him. "...I'm sorry...goodbye, Erin..." Then he straightened and started to walk into the woods. "Come on. Let's go get the others...then we can go home..."

* * *

><p><strong>So this chapter is kinda short and it took a few days, but i rewrote this chapter few times. Writer's block is my mortal enemy. Well, you know the drill! Please review and I'll try to update soon. Till then!<strong>


	5. Captured

**Chapter 5 Captured**

* * *

><p>Erin jumped up and slid her legs through two slots of her cell so that she hung upside down. Then she began doing crunches. By the time Tiger Claw came to her cell, her tank top was soaked in sweat. She hopped down and wiped at her forehead.<p>

The giant feline put a bowl on the floor and slid it into her cell with his foot. Erin wrinkled her nose. It was filled with some kind of meat that looked like it had gone through some attempt at being cooked enough to make it edible, but the attempt didn't seem successful. She sighed. "I can only eat meat like _that_ when I'm a wolf, cat."

Tiger Claw growled. "Well, it's all you're getting, pup." He turned and stalked off. "Master Shredder always keeps such ungrateful whelps in his dungeon." Erin scowled at his retreating back in annoyance.

She regarded the meat and sighed. She'd have to wait until she became a wolf again to be able to eat that. It'd probably just give her heartburn or indigestion or something if she ate it while in her human form.

Angrily, she shoved the bowl away and sat on the ground. The bowl rocked side to side before settling and it may have just been her lonely mind conjuring up cheerful images, but she could have swore the meat had flopped over to look like a little turtle. It didn't look like one of her mutant friends, she hadn't gone crazy just yet, but a little baby turtle you might find in the woods. Erin sighed and began to draw in the dirt with her finger. Exercising tired her, but it left her mind free to think. She couldn't afford to think right now. Then she noticed what she had drawn. It was a tiny heart with a D and an E in it. Erin decided to give in and drew a staff on the heart, then little wolf ears and a tail. It was a little odd, but it made her smile. She needed a smile right now. This was worse than last time...because this time there was someone that made her ache to be free and to stand beside him... Erin sighed again and began to do some meditation to clear her mind...as if she actually could clear her mind...

* * *

><p>Donnie flicked a pencil back and forth across his desk. "Ahh!" He made an angry cry and swiped his arm, making a bunch of loose papers fall off his desk in a flurry of movement and flutter to the ground like loose autumn leaves. Donnie pushed away from the desk and paced. He rarely got this angry, but how could he not be? Shredder had hurt someone else he cared about.<p>

When they had gotten back, they had briefed the others and Donnie had retreated to his lab as soon as possible. He needed to be alone, not even staying long enough to see Splinter and Karai's reunion. Ever since they had met up with his brothers in the forest, Donnie kept replaying the moment from when he had first found Erin in the sewers to when she had been taken from his view. Donnie slowed in his pacing. Now, as he replayed that flashback for what felt like the hundredth time, alone in his lab, he felt his mind stutter and pause on Erin's kiss. He sighed sadly. It had felt wonderful, but then she had pushed him away. No. She had pushed him to safety. Wait... Donnie's brow furrowed. Before Erin had shoved him away...before she had kissed him... He looked down at a small plastic rectangle clicking off his shell. Now, he remembered. She had clipped something to his strap, but he had forgotten because it was right before she had kissed him. The moment had gotten eclipsed, but now he remembered.

Donnie unclipped the item from his strap and looked at it closely. It was a small black rectangle with a small white paw print on it. He turned it over in his palm and hit a small button on it. Out shot a small rectangle that he instantly recognized as a USB port. So, it was a flash drive? Interesting. He hurried to his computer and plugged it in. His computer wasn't top of the line, so it took a moment for the computer to recognize the small device. It was only a few seconds, but it felt like years had passed before he had the menu pop up.

As he waited, there was the faint creak of the barn door opening. "Donnie...? You doing okay...?" Leo approached his brother and leaned in to look at the screen, realizing whatever it was must be important if Donnie was so entirely focused on it. Donnie and Leo stared at the screen intently as they tried to figure out what secrets the flash drive held. There were various folders and when Donnie opened them, they briefly saw a variety of documents, pictures, and videos, but there was a video on the main menu that was labeled 'watch first' so he clicked it, after a supportive nod from Leo. No words even needed to be said, not yet.

The video took a moment, but after it loaded the brothers were watching what seemed to be a lab. Stockman-fly buzzed around and they watched as he hit a buzzer and some foot-bots came in. One held a length of chain while the other two walked on either side, like guards. The chain was connected to a sturdy looking collar on a jet black wolf. At first Donnie thought it was Erin, but the wolf was small and not as muscular as she was. Yet... "It's Erin."

Leo looked at his brother startled. "Donnie, I know they look close, but..."

"No. It's her." The wolf in the video was digging its paws into the ground and was snarling, lips pulled back from deadly looking teeth. It shook its head, trying to resist being pulled, but the foot-bots prodded it along. At one point, the wolf turned and snapped its jaws on one of the robot's arms and yanked, tearing it free. It was that instant, when the wolf looked up and Donnie saw the wolf's eyes...he knew it was _her._ She tossed the arm aside, but before she could attack again, the lead foot-bot yanked her into a glass cylinder. It shut behind her and even though she slammed herself against the glass and pawed at it, it wouldn't break. Her claws left scratches, but the glass stayed solid.

Leo jabbed a finger at the screen and Donnie tore his eyes away from Erin's helpless form. "Look, Donnie. Shredder." Shredder had walked into the lab and regarded Erin's angry form, she stood glaring and growling at him, before he approached Stockman-fly.

"Is it ready?" Shredder gave his minion a look that made the only response that wouldn't result in bodily harm be 'yes, sir.'

"It is ready, master Shredder." The fly buzzed up and yanked a cord. Over the cylinder, a tarp filled with mutagen came loose over the wolf. She reared up on two legs and fell back heavily, twitching as the first few sprinkles hit her. Then the tarp covered her body and the mutagen oozed all over her. There was a slight rustling beneath the tarp and then it was still. Finally, Erin's head poked out, wolf eyes staring out from a human head. She looked exhausted and promptly collapsed. Stockman-fly turned to Shredder and spoke cheerily. "Phase one is complete. Now I can begin phase two." Then the clip ended.

The turtle leader straightened and rubbed his head in confusion. "So...Shredder turned Erin into a mutant that becomes a human or at least had Stockman do it. I wonder why..."

"I know why." Donnie rolled his chair to the side and pointed to a document he had pulled up. "Shredder wanted an animal that could be a human mutant so that he could use it as a test subject."

"But what did he want to test?"

Donnie scanned the page, but quickly found the answer. "She was a test subject for Karai. Shredder wanted Stockman to use Erin as a test subject so he could turn Karai human again." Donnie's eyes widened in shock as he read. He was used to staring at a computer screen for hours on end so naturally he read it a lot faster than Leo. "Oh, no..."

"What?" Leo looked between Donnie and the screen that Donnie was scrolling through so fast that he could hardly read even a few words.

"It's...it's Stockman's notes on all his experiments..." Donnie closed out of the document and put his head in his hands.

"So? Isn't that normal for scientists?" The blue masked turtle regarded his brother, confused.

"You don't get it, Leo. It's Stockman's notes on _all_ his experiments. He's put Erin through dozens of experiments and now that they have her he'll do more experiments to her..." Leo silently absorbed this chilling information as Donnie clicked through some more documents. At one point he found a picture of Erin in what seemed to be a sleeveless black dress. It wasn't fancy, but rather plain and somehow seemed sad. In the picture, Erin had long tentacle-like appendages extending from the circles on her arms. "So, this must be how she knocked out master Splinter." The brothers read through about Erin's unique ability, until Donnie gasped. "That's why she needed Karai's blood!"

The turtle leader looked at his brother exasperated. "Donnie, you keep losing me! Why? Why did Erin need Karai's blood?"

Donatello's expression softened at the realization. "She was going to absorb it and once she did, she'd be able to control her shifting. Karai can shift on will so when Erin absorbed some of her blood she'd be able to shift at will too."

Donnie was clearly ecstatic at the revelation, but Leo looked at him carefully. "Donnie...if Erin can shift at will...well, we saw that initially she was a wolf..."

"So?"

"So...if she can become a wolf by choice isn't there a chance she'll just stay a wolf? There's no guarantee she'll stay here when out there is her home. Donnie...I know you care about her...but she was only here a couple of days. She'll always be welcome here, to me, but she was taken from her home and this isn't it..." This was one of the things Leo always hated about being leader. He always had to realistic, putting a stomp on his brothers' wishes and dreams at times. He could see the sadness in his brother's eyes as he took in what he had just said, but then Donnie clenched his fists and looked up at his brother determinedly.

"Then that's her choice, but we still have to save her, Leo."

Leonardo smiled at his brother. It was tough being the leader, sure, but when his brothers didn't resent him for making the choices he did, it could be a very rewarding job. "Let's go round up the others."

* * *

><p>Splinter watched his sons with pride as they discussed how best to save Erin. Donatello wasn't letting his feelings get in the way, Raphael wasn't letting his temper get the best of him, Michelangelo was actually being fairly serious, and Leonardo was patiently thinking out different approaches with his brothers.<p>

Casey glanced up at Splinter from where he sat off to the side. "Do you really think they can save her? The city is crawling with Kraang and Shredder is seriously tough after all."

"My sons have overcome a great deal and they have conquered many challenges and adversaries I would have had doubts about." His gaze fell on Donnie. The turtle tapped his chin then drew on the map they had laid out on the coffee table. "Their judgement is much clearer and more focused than it once was."

Casey nodded. "Yeah, but we all know that Donnie is digging on the she-wolf. Don't you think that'll hurt the mission or whatever?"

Splinter paused, considering this. "Motivation is crucial to completing any goal and Donatello has more motivation than his brothers due to his feelings. I have faith in my sons to do what's right and not rush into battle unprepared." With that, Splinter walked into the kitchen in search of a snack, preferably with cheese.

"Alright then." Leo made one last note and nodded. "Everyone set on what to do?"

"I still don't see why we have to sit out. Again." April crossed her arms in annoyance.

"April, the Kraang are still looking for you so it's not safe to have you so close to them. The four of us can handle things. Besides, thanks to Donnie's web feed and the t-phones you can monitor things anyway." The girl still looked at him in irritation, but Leo didn't see much choice in the matter. "Look. April, you're strong and a good fighter, but it'll be dangerous for even us four to go back into the city. I'm not going to risk more people than necessary. The fact of the matter is Donnie has to go, there's no stopping him on this, and Mikey has already told us how determined he is to go. As for Raph, he said he wants to go too and he's our strongest fighter."

April looked like she might argue more, but then a hand fell on her shoulder. She looked to its owner and saw Casey looking at her. "C'mon, Red. It's their mission and it just makes sense, even to me." April nodded and as Donnie watched their exchange he realized this was the first time he was seeing Casey and April have a moment where he didn't feel intense jealousy. The jealousy was there, but it was more like a dull throb. It felt strange, but not so strange when his hand unintentionally brushed the flashdrive on the table. He picked it up, studying the small pawprint. Was it...could he really be developing feelings for Erin...? He was so unsure, yet the idea was starting to seem more possible and more desirable.

"Alright, team." Leo stood up. "Let's move out."

"Good luck, my sons." Splinter nodded to his sons.

They headed outside to the party wagon where they were startled to see Karai, standing and leaning against the side. She looked up as they approached, her expression determined. "I'm coming with you. No debating. Erin, helped me get free, so now I need to help her."

Splinter strode ahead of his sons and grasped her shoulders. "Miwa...I just got you back...I can not lose you again..." For once, the man's eyes and voice were pleading, showing just how desperate and helpless he was.

Karai actually looked like she might back down so Leo stepped toward her. "Karai...if the mission goes wrong, we'll need solid back-up and you're a strong fighter. Splinter is right. We can't lose you again. So just this once, please, just stay here and let us handle things. Please."

Karai stared at Leo with her odd snakelike eyes that were so filled with pain and she nodded. "Alright, but if you guys don't come back, I'm going in after you and kicking your butts after I rescue you."

Leo grinned. "Deal."

* * *

><p>The dungeon was quiet except for heavy footsteps. Tiger Claw dragged Erin along the ground by the back of her shirt, not showing any care or gentleness. The humanoid feline tossed Erin back into her cell and she fell on the floor with a thud, just laying where she had fallen weakly. He snorted in something similar to amusement then left after closing and locking the door.<p>

"Uhhhhh..." Erin groaned softly. She was so exhausted... The girl tiredly made a sound again as her body shifted. She stood once she had shifted and shook her fur out. Erin sighed and laid down, resting her chin on her paws. The scent of meat captured her attention and she raised her head curiously. Somehow the nearly raw meat that had made her stomach churn to consider eating as a human made her lick her lips eagerly as a wolf. She moved to the bowl and grabbed it in her teeth. The wolf retreated to the corner of her cell before laying down to enjoy her dinner. Whatever it was, the meat was fairly raw, but tasty to her wolf stomach. It had been sitting in this dank and dark dungeon for a while, but it was still okay to eat. She yawned and curled up to sleep, but her body ached and she knew sleep wouldn't come easy.

To make matters worse, there was this awful collar she had now. Due to Baxter's experiments, he had realized showering her in more mutagen at this point wouldn't have much, if any, of an affect on her. So the collar was programmed to shock her if Baxter wanted and if she tried to break it, she'd be covered in retromutagen. For so long, she had wanted just to be a wolf again, to run wild back in her forest, but now she realized she didn't want that. That's why Rahzar had explained to Shredder how she had kissed Donnie and sacrificed herself for him. Shredder knew just as well as Erin the awful truth: if she became her old self, she'd likely forget all about the turtles. Some memories and things she wouldn't mind losing, but all her memories of her friends? Her memories of Donnie? Erin let out a low, sad whine. Maybe she'd remember, but could she fight her instincts? Being a mutant, even now when she was a wolf, she could think human thoughts that a purely wolf brain wouldn't even consider. She always had her animal instincts, but in her wolf form, her instincts were stronger. Would they overpower her if she became a complete wolf again? No...she wouldn't be complete if she was only a wolf again. The most her instincts would ever allow would be to silently watch Donnie and the others from the edge of the woods, a golden eyed shadow in the forest. She wouldn't be complete if that was what she was.

What did it even matter? She had been here for days and it'd be ages more that she'd be here, with more tiring and painful experiments. Erin stood and paced, her body packed full of tense energy. If she broke the collar...she'd lose her human side and all its memories, but wouldn't it be better than being trapped here? A wolf would just snarl and attack until it was free and could fade into nature. Wolves weren't as vicious as many thought, but back any creature into a corner, trap it, and it'll fight.

"Restless, aren't you?" She spun to the door. Rahzar grinned at her. He looked like some skeletal mishmash, but he was still a dog. Her ears pressed against her skull and she let the growl in her belly slip from between her bared teeth, rumbling through her whole body. Rahzar raised his eyebrows in surprise then snickered. "Feisty." He opened the cell, coming inside, and now all Erin's instincts were screaming to 'run! get away!' Rahzar was bigger and stronger, plus she was still exhausted from all Baxter's experiments. She jumped back and snapped at the air between them. "Stupid pup." Rahzar swung a paw and batted her. Erin hit the wall and fell to the ground with a whimper. He was fast...too fast! Usually she was fast enough to keep up with someone even as fast as him, but her body was too sluggish and begging her to lay down and rest. She was NOT up to a fight.

The bigger dog grinned and grabbed her, pinning her back to the wall. She whimpered, her front paws trying to scratch at his hand, while her back paws uselessly tried to find purchase on the wall or floor. "This is no fun when you're so weak. You were a lot tougher in the sewers. Was it because you were human? Nah. Humans are weak. Us, animals? We're strong. So maybe...if I broke this..." His free hand found the collar on her neck and Erin froze in her struggling as he pinched it. Her heart raced. He was easily strong enough to break it...she still didn't know if she wanted that or not, though. With a growl, she twisted her body in a way that was so unnatural for a wolf to move and yet in her human mind it seemed to fit perfectly. She twisted and snapped her jaws shut on Rahzar's hand holding her collar. He screamed and yanked his hand away from her. Erin glared at him with a challenge, but he was more focused on his injured hand. "YOU!" He roared in anger and yanked Erin away from the wall. Her eyes widened in shock, but only for a instant because he yanked his hand up as high as he could before slamming her down into the cell's rough stone floor. Erin made a startled, pained noise as her body hit the rough surface. She stood to flee, but then the edge of her vision began to blur, making her stagger and fall.

"Master Shredder can find a new test subject...after all...when you tried to attack me, I had to defend myself. So tragic..." The giant hand wrapped around her middle slid away, almost gently, but her body still lay limb on the ground. Erin's mind weakly knew, somewhere deep inside, that she should get away. She had to MOVE! Rahzar wrapped a hand around his fist and with the last of her strength, Erin rolled her to head to the side. One golden eye watched as Rahzar raised his hands, getting ready to end things. Erin couldn't even properly get scared, her brain was still fuzzy from hitting the stone. So this...this was it... That was all Erin could think. Well, that and Donnie. Time seemed to slow down as Rahzar stood over her, but that was probably just her damaged body. Nonetheless, Erin took advantage. She fantasized that Donnie jumped up behind Rahzar and cracked him over the skull with his staff before rushing to her side. Wouldn't that be wonderful... She wished she could have kissed him more...but she hadn't and it was too late now. Oh, well...too late now...

Then there was just a loud crack and everything went dark.

* * *

><p><strong>Chapter 5 now done! Woo! Hope you guys liked it. My main concern for this chapter was if it got too intense and out of the whole tmnt world, so let me know guys! I think it was okay, but let me know. Please review and tell me what you think overall too of course! Thanks everyone!:D<strong>


	6. Exhaustive Rescue

**Chafter 6 Exhaustive Rescue**

* * *

><p>She was so tired... Her body hurt and ached all over and she was shaking badly. Distantly, she realized someone was calling her name, but she was too tired to care. She just wanted to sleep...<p>

"...ri..." No...she wanted to sleep... "...Erin..." Erin stirred and realized she wasn't shaking. Hands were holding her and were shaking her. "ERIN!" The hands grasped her firmly and then water was splashing her in the face. She gasped and stood, but her body was still weak and she staggered, the hands catching her and their strong arms held her up. "Easy..." Erin looked for a face, but her vision was still too blurry. She sniffed the air and realized who it was. She whined and licked his cheek lightly. She could almost hear the smile in Donnie's voce. "Yeah, I missed you too..." Erin heavily leaned against him, her strength nearly nonexistent. Her thoughts were fuzzy, but she kept thinking 'Donnie came...he's here..."

"Booyakasha!" Mikey whacked Rahzar over the head with his nunchucks. Rahzar roared in pain as Raphael swept his legs out from under him. The large dog fell and Michelangelo jumped on his back, making the skeletal dog's head bounce off the stone. He hit it hard and slumped to the ground, unconscious.

"How is she?" Raphael and Mikey ran over to Donnie and Erin.

"I'm not sure. She's really weak, though." Erin growled softly as if to confirm what he had said.

Raphael spun his sais then gripped them firmly. "Well, we have to move. Donnie, do you think you can carry her?"

"I think so... Mikey help me get her on my back." The youngest turtle moved behind Donnie and they lifted Erin on to Donnie's back. He held her like he would if he had to carry a person on his back so it was a bit awkward to hold her, but she was big enough that her front legs hung over his shoulders, giving him a bit of balance. She growled weakly against his ear and he could feel her body vibrate with the noise. "I've gotcha."

"Come on! Foot-bots will be here any moment." Raphael scanned ahead and then the three brothers ran forward.

They hurried silently until they came to a threeway tunnel path. The brothers scanned all three tunnels uncertainly. Mikey's eyes widened. "Which one?!"

"I don't know!" Raphael clenched his hands around his sais angrily. This is exactly why he had wanted Leo to come along. He couldn't lead this team, had tried once before and failed miserably at it, but Leo was still injured and in no shape to sneak into Shredder's lair so he was their 'getaway' driver of sorts and supervising from the party wagon. Even with that, Raph was the one that had to make decisions in the field.

Donnie was frantically looking at his brothers as a slender tentacle slid up and pressed against his upper arm. (Take the left hall...) Donatello looked around in confusion for the voice seemed to just ring in his head. He heard a weak laugh in his head. (Donnie...it's me.)

"Erin...?"

(Yes. When my tentacles connect me to someone, I can mentally communicate with them. Now come on. We have to hurry.)

"Guys! Erin says we should take the left tunnel." Raphael and Michelangelo looked to their brother and were startled to see Erin's tentacle latched on to his arm and to see Erin staring intently over his shoulder with a serious gaze.

"No one has any better ideas. Let's do it!" Raphael charged ahead followed closely by his brothers.

(Take a right...)

"Raph! Take the next right!" The brothers swerved and sure enough there were footsteps from the left tunnel. Donnie whispered so only Erin would hear. "How do you know which ways to go...?"

(I was here for a long time, Donnie...and I uploaded maps that were on my flashdrive that I loaned you. Those maps I have memorized. They were my escape routes.)

Donnie nearly collided with Mikey as his brother stopped dead in his tracks. Raph was frozen too. "Guys! What's going..." Donnie trailed off as he saw what had stopped his brothers...

Shredder...

"Well, if it isn't Splinter's pet turtles..." His gaze fell on Erin. "And it appears his pets decided to free the wolf pup as well..." His blades extended and the turtles could feel their blood turn to ice. "Well, if you want something done right..." He raised his blades and looked between them at his adversaries. "Eliminate it yourself."

Erin had been sapping energy from Donnie so that she would be able to run and wouldn't have to rely on him. She had felt bad for taking his energy, even if it seemed like his stamina was limitless, but now she didn't feel as bad. They would need all the fighting power they could against Shredder. (When I give the signal...help.)

"What are you...?" With a growl, Erin pushed her weight forward on Donnie's shell, making him lean forward. She quickly pressed her paws to his shell and launched herself at Shredder. Everyone, the turtles and Shredder included, looked at her startled, so she had the element of surprise. The large wolf hit Shredder, hard, and the pair went rolling on the ground. Erin began snapping at Shredder, twisting this way and that as she tried to grab hold of him. She truly looked like the stereotypical vicious wolf. Shredder was too quick and her teeth didn't manage to find purchase, but her teeth scraped his mask, managing to pull it off.

"Savage beast!" Shredder punched Erin hard in the jaw making her skid back on her side with a whimper.

"Booyakasha!" Mikey swung his nunchucks at Shredder as Raph advanced with his sais. Donnie rushed to Erin, but before he could reach her, she had sprung to her feet and jumped back into the fray. Mikey and Raph were giving their all, but they were still only holding Shredder off, and barely at that... Erin realized this and their time was short before more foot-bots showed up or more of Shredder's evil, mutant zoo. Silent as a shadow, she slipped behind Shredder, but the scuffle was too chaotic. She gritted her teeth. Things weren't going to well...they would need to end this fast. She'd need time to use her mutagen powers, as draining as it'd be. The teen really didn't have the energy to spare...but she didn't have a better plan.

Erin narrowed her eyes and waited. She needed to time this just right. Raph jumped over Mikey and clashed his sais against Shredder's blades. Shredder had to take a moment before he could throw Raph off. As he did, it exposed his neck. With a growl, Erin shot out a tentacle and it latched on to his neck.

"What the...?!" He pulled at it uselessly, then his eyes found Erin, crouched angrily, and he narrowed his eyes in anger. "You..."

(Me.) Erin snarled and Shredder collapsed.

The brothers stared in shock. Mikey timidly spoke up first. "Is he...?"

"No." Donnie looked at the others as he found Shredder's pulse. "Just knocked out. Right, Erin?" She nodded then gestured with her head.

"Guys? What's going on? You haven't moved for a while."

Raph picked up his T-phone and responded to Leo's worried voice. "We ran into trouble, but there's no time to discuss it. Which way, Leo?"

"Ummm...hang on..." Erin barked and gestured down one tunnel with her head again.

"Let me guess...middle path?"

"Yeah! How'd you know, Raph?"

Raphael smirked. "Lucky guess." Erin rolled her eyes, then the group hurried down the tunnel.

Erin had impressive stamina due to her mutated state, but she had still been quite drained. It surprised her that she still had energy enough that she could run alongside the turtles. Still...she wasn't going to last much longer. She let her wolf side take over the task of running. The monotonous task was easy for the wolf and she didn't have to dwell on the pain this way.

They came to a few more junctions, but before long they were back on the street. Everyone was breathing hard, but Erin's legs were shaking slightly from the overexertion as well. Donnie crouched and rubbed her head. "You can rest soon. I promise."

"Guys, c'mon!" Mikey waved them to the sewer entrance as Raph jumped into the opening. Donnie and Erin hurried inside before Mikey dropped into the hole, the manhole covering sliding back on top right before a few Kraang controlled zombies walked by. One glanced at the cover before following after the others.

* * *

><p>"Guys, hang on." Donnie looked at Erin worriedly. She was panting and her legs were still shaking, but it was even worse now.<p>

"What's wrong?" The brothers hurried back and Mikey patted her head. She looked up at him with a tired expression and she looked ready to collapse. "You okay, Erin?"

"C'mon. I'll carry you again." Donnie crouched to let her climb on and Raph silently watched before giving his brother a shove that nearly sent him toppling into the sewer water. "What'd you do that f...?!" Donnie paused as he saw his brother, crouched like he had just been.

"You were carrying her earlier so you'll just slow us down if you carry her again now."

Mikey seemed just as surprised as Donnie. "But, Raph, what if we get in a fight?"

"It's the sewers, Mikey. Besides, I can just put her down. Erin, get on." With a nod, the wolf scrambled on to the turtle's back. Then they were off again.

Before long, the mutant teens reached the exit and they jumped out of the opening. Erin gave a startled whimper when Raph landed as her injured jaw snapped shut at the impact. "Sorry, Erin." She gave a soft accepting whine in the turtle's ear.

"Where's Leo with our ride?" Mikey scanned the area impatiently.

They only had to wait a moment before their leader drove up. "Anyone need a lift?" Leo grinned at his brothers until he saw Erin's condition. The smile fell off his face and he nodded at the back. "Everyone climb in. Donnie, you can check on her on the way to the farmhouse."

* * *

><p>Everyone was quiet as Leo drove, the tension in the air nearly tangible. Donnie was checking Erin over, but his specialty was machines. He barely qualified to be the group's makeshift doctor and the turtles' physiology had become closer to a human than an animal, where as Erin was an animal at the moment. He could only check the basics and felt fairly helpless as he watched Erin's ragged breathing.<p>

Mikey scooted closer and looked at Erin worriedly. "Is she gonna be okay, D?" Erin licked his hand and gave a reassuring smile at him, though she didn't take her head off her paws the whole time.

"It seems like she'll be okay...but I'll have to treat her a bit when we get back to the farmhouse. She's too stubborn to stay sick." The purple masked turtle patted the wolf's head affectionately and felt her vibrate with a happy growl.

Their leader called from the front seat. "Well, that'll be in just a minute because the farmhouse is at the end of this road." Leo turned on to the dirt road and drove along.

It just took the group a few minutes before they reached the house. As Leo turned the van off and they started to climb out as the others came out of the house, nervous expressions on all of the faces. The sun was rising, adding an eerie red and orange glow to everything. It made everything seem fairly ominous.

April reached them first as Mikey and Raphael climbed out of the back. "Is everyone okay...?"

"Everyone is fine, April." Leo smiled as he hobbled over. "Erin, is pretty beat, but should be okay after a little rest. Right, Donnie?"

"That's my diagnosis. Casey, can you help me carry her inside?" He noticed her eyes flicker to Karai and he stroked her head. "Let's get you inside first..." She nodded. She'd been patient this long. Besides, she really was exhausted. The wolf closed her eyes and finally let herself slip into unconsciousness as she transformed back into a girl.

* * *

><p><strong>Hey, guys! Been a while. Feel free to toss me in a tank of mutagen for my extended absence. One thing led to another and my old copy of this chapter got deleted...it was a mess. Hopefully this one is alright, but as always tell me what you think! Again sorry for the wait guys!<strong>


End file.
